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It looks like the wiring on the 2.5 intake manifold wont work on my 94 legacy, ill have to move a couple things from my 2.2 intake but it should work.

Ive tested the connections and such, So My question is even though the plugs plug in and into the injectors will the fact that the legacy being sidefeed altar anything since the ej25 is topfeed, there the same plugs..

Take the harness off the original motor (the one that matches your Legacy harness). Then go through the sensors and injectors to ensure the right plug shapes are there. IIRC, the top feed injectors need to have the little locating tab ground down to fit the sidefeed harness plugs, or you can cut and splice, or repin them to match.

I used my old engine harness so it would plug into my wiring harness. I just spliced in the plugs from the new harness on to my old one. Most likely you will have to use your 2.2 throttle body, in doing so you will have to make an adaptor plate to go between the 2.2 throttle body and the 2.5 manifold. This is easily done. I used a piece of 20 guage sheet metal and made a template for the adaptor off of the 2.5 throttle body gasket. Just do not cut a hole for the port in the top of the gasket. When you are done you should have the 4 holes for your bolts to go through and the large center hole for the air flow. Use permatech to seal the 2.2 gasket on the throttle body side of the adaptor and the 2.5 gasket to the manifold side. Mount the throttle body onto the manifold an your good to go.

Okay i think im on the right path but im a little confused about the injectors and throttle body, What your saying is swap the harnesses, make a spacer for the throttle body and a ground for the injectors, Cacn somebody clarify a bit?

Take the harness off the original motor (the one that matches your Legacy harness). Then go through the sensors and injectors to ensure the right plug shapes are there. IIRC, the top feed injectors need to have the little locating tab ground down to fit the sidefeed harness plugs, or you can cut and splice, or repin them to match.

Jay Storm

So easiest route is, Splice the injector wiring (Thats pretty EASY, two wires a piece, or is it three a ground)

yep basically just change the injector plugs, 2 wires a piece. you may also need to change the plug on the water temp sensor. On the old style it was 2 plugs ( a 2 wire and a single wire). On the new style it is 1 plug with 3 wires. Wire the 2 wire into the top 2 wires iof the triangular plug and the single wire onto the bottom pin of the triangular plug. The bottom wire is your temp guage sensor. So;

1) Make the adaptor for the throttle body
2) splice the new fuel injector plugs onto the old harness (put a piece of tape on one of the plugs on each side so you know which plug goes to which cylinder-VERY IMPORTANT!)
3) Splice in the plug for the water sensor and temp guage.
4) You will need to use the 2.5 coil pack, (unless you want to have custom wires made- ugh!) The 2.5 coil pack has the ignitor integrated with the coil. This means you have to bypass the ignitor that existed in the wiring harness before since it is not needed anymore. Here are the directions for doing so;

Step 1. Cut off connector for ignition coil from 2.5rs harness. save some wiring to extend from 1.8 harness.

Sounds like some great info, except the fact i dont have a 1.8, you mean 2.2 right?

Here are the pics of what i think your thinking of..

your talking about the fact that the coil pack sensor dont match up right?

So i use the wires from my stock ignitor with the 2.5rs coil pack connector correct, since on the 2.5 there integrated and on my 2.2 they are not correct? So all im doing is merging my ignitor wires with the coil pack wires since on my legacy there separate.

Also the Coolant sensor is on the main hardine right? when i looked for it on the 2.5 it wasent there, or is it in a diffrent location?

So this is the coil pack connector right? Also the connection on the intake is just a ground right?

This is my stock coil pack connector, So all i have to do is splice 2/4 wires?

1st does your car have a separate ignitor mounted at the back of the engine bay in the center? If it does then you need to follow the instructions posted above for bypassing the ignitor. You will then splice the 2.5 coil plug onto your old engine harness, there will be an xtra wire which will be the ground. You can ground that anywhere you want.

Yes, in the first picture the black wire mounted to the manifold is a ground.

I suggest taking the 2.5, removing the manifold, then removing the eniring harness from it. Then start routing the 2.2 harness onto the 2.5, you will find that both harnesses are very similar. This will give you a place to start and a visual guide to what still needs to be hooked up.

BTW is this a SOHC or a DOHC 2.5?

Storm was talking about an alternative to splicing in the injector plugs. You can gind down the little ears on the plugs so they will slide over the new injectors. The old plugs have the tabs/ears in a different place. Try to plug in one of the new injectors using one of the older 2.2 plugs and you will see what i'm talking about. I found it easier to just splice the newer plugs onto my older harness.

Lastly with grounds all you have to do is make sure they are grounded. So ground them where you want, just make sure they have a good connection to the metal.

Once you start laying out your 2.2 harness on the 2.5 block it makes good sense, you can see what goes where by the location. Just pay attention when you remove the harness from the 2.2 manifold as to what goes where. I think the injector plugs that have the white tape on the wires by the plugs go tward the front of the engine to cylinders 1&2. When you splice these plugs onto your harness make sure you mark which ones go in front on each side to you dont mix them up.

Lastly, The triangular plug you are looking for on the 2.5 is (looking at the engine from the back) just to the right of the throttle body below the manifold. Once you remove the manifold you will see it. Its the only triangular plug on the 2.5.

ok the first part is the plug that goes to the coil pack, look at the plug with the clip thingy pointing up, splice the plug onto your harness by attaching the wires from left to right. I believe your colors should be the same. The 3rd pin from the left will be the ground so no wire is spliced onto it, just ground that one to a bolt on the manifold.